Firepower Threat Defense
CVE-2023-20270
MEDIUM
Severity by source
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
Lifecycle Timeline
1DescriptionNVD
A vulnerability in the interaction between the Server Message Block (SMB) protocol preprocessor and the Snort 3 detection engine for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the configured policies or cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper error-checking when the Snort 3 detection engine is processing SMB traffic. An attacker could exploit this vulnerability by sending a crafted SMB packet stream through an affected device. A successful exploit could allow the attacker to cause the Snort process to reload, resulting in a DoS condition.
AnalysisAI
A vulnerability in the interaction between the Server Message Block (SMB) protocol preprocessor and the Snort 3 detection engine for Cisco Firepower Threat Defense (FTD) Software could allow an. Rated medium severity (CVSS 5.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified under CWE-20. A vulnerability in the interaction between the Server Message Block (SMB) protocol preprocessor and the Snort 3 detection engine for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the configured policies or cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper error-checking when the Snort 3 detection engine is processing SMB traffic. An attacker could exploit this vulnerability by sending a crafted SMB packet stream through an affected device. A successful exploit could allow the attacker to cause the Snort process to reload, resulting in a DoS condition. Affected products include: Cisco Firepower Threat Defense.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Same weakness CWE-20 – Improper Input Validation
View allSame technique Denial Of Service
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External POC / Exploit Code
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